How Sound Editing Works

Now almost all sound editors use computerized editing systems called digital audio workstations (DAW). Digital audio workstations are multi-track systems that greatly simplify and enhance the sound editing process for all types of professional audio production (film audio, studio recording, DJs, et cetera).

Digital audio workstations vary greatly in size, price and complexity. The most basic systems are simply software applications that can be loaded onto a standard personal computer. More professional systems, like DigiDesign’s Pro Tools, require a special sound card and are typically used in conjunction with large digital mixing boards and are compatible with hundreds of effects and virtual instrument plug-ins. The advantage of all of these systems is that an editor can work with all kinds of audio files -- voices, Foley clips, analog and MIDI music -- from the same interface.

The basic sound editing process hasn’t changed much in the transition from magnetic tape to hard drive. Each element of the film’s audio is still edited as individual tracks (dialogue, effects, music). But with digital file formats and increased computer processing speed, the total amount of tracks is limitless. Besides multiple dialogue tracks, an editor can add dozens of background effects and layers and layers of Foley and music. Multiple tracks can be cut, copied, pasted, trimmed and faded at once. And each track comes with dozens of controls for volume, stereo panning and effects, which greatly simplifies the mixing process.

One of the big advantages of digital audio workstations is that they allow sound editors to work with graphical representations of sound. With magnetic tape, everything was done by ear. Now editors can look at the sound waves on the screen. They can see extraneous background noise and remove it with a click of the mouse. Some DAWs can automatically clean up audio, removing clicks, hisses and low-level background noise that would have ruined a take in the old days.

With graphical interfaces, sound effects designers can study the waveform of a sound and easily bend and distort it to create something completely new. A lion’s roar can be stretched and pitched down to become the bellow of a tremendous sea monster. Newer DAWs even let you control surround sound through a graphical interface. Drag the control to the back left of the screen and that’s where the audio will appear in the theater.

Some DAWs are designed especially for film and video professionals and include the ability to sync audio with film or video clips. This is especially useful for scoring a film or for adding detailed Foley effects that need to be timed precisely with the on-screen action. These systems also allow you to export audio in standard surround sound formats like Dolby 5.1.

For even more information on sound recording and related filmmaking topics, check out the links below.